Marine Organism Transforms Mediterranean Beaches, Boosting Tourism

The return of Amphistegina lobifera to the Mediterranean Sea is a silver lining in the face of climate change, turning rocky beaches into sandy tourist destinations and highlighting the dynamic relationship between human activities and marine ecosystems.

In an unexpected twist, a species of microscopic marine organisms, foraminifera (forams), is reshaping the future of coastal tourism in the eastern Mediterranean. Amphistegina lobifera, a single-celled organism known for its calcium carbonate skeletons, is transforming rocky shorelines into sandy beaches, offering a surprising economic boost.

Pamela Hallock, a distinguished university professor of geological oceanography at the University of South Florida College of Marine Science, has dedicated her career to understanding the impacts of human activities on marine environments. Typically wary of the effects of climate change, Hallock found a glimmer of hope in her latest research.

“These forams have been increasing in numbers in suitable environments,” Hallock, a corresponding author of the study, said in a news release. “Now they’re so prolific that they’re becoming an economic resource in regions with warm waters and high alkalinity because they’re building beaches.”

The discovery stems from Hallock and her team’s research published in the Journal of Foraminiferal Research. Forams like Amphistegina lobifera first made their way into the Mediterranean Sea via the Suez Canal 60-80 years ago. Now, they are flourishing, particularly in the nutrient-poor waters of the eastern Mediterranean, and are moving westward. While their invasive potential has raised concerns, their impact on tourism is turning out to be remarkably positive.

In countries such as Turkey, beaches that were once dominated by rugged volcanic and limestone rocks are now covered with up to a half meter of sand, primarily made up of dead foram skeletons and other shells.

“The rate at which these forams are building beaches in the region is comparable to the rate of sea level rise,” added Hallock.

The significance of this transformation extends beyond the immediate economic boost from tourism. Amphistegina lobifera’s ability to flourish in warm waters with elevated levels of CO2 could indicate a broader ecological shift as climate change progresses. The genus Amphistegina, which emerged during a period of higher atmospheric CO2, thrives in environments with high alkalinity and temperatures, making current and future Mediterranean conditions ideal for their growth.

Interestingly, Amphistegina lobifera’s presence in the region could be seen as a return to its ancestral waters.

“These are a kind of critter that previously inhabited the region,” Hallock added. “Now, through our influence on the environment, we’re making the habitat once again suitable for them.”

This development offers a nuanced perspective on the ongoing interplay between human activities and marine ecosystems. As Hallock and her co-authors pondered in their study, “Might this return of prolific shallow-water carbonate production ultimately prove at least locally beneficial as climate change progresses?”

The findings underscore not just the adaptability of marine life but also the potential for unexpected benefits amid environmental upheavals, providing a poignant reminder of nature’s resilience.